bugfix: add fix for istio on multi-cloud playground

[alaye-ms]

Upgrade istio version on the multi-cloud playground, and also add a workaround for the webhook for fleet.

[Copilot]

Pull request overview

This PR updates the multi-cloud playground Fleet/Istio setup to improve multi-cluster deployment reliability by upgrading Istio and adjusting how Fleet placements and admission webhooks behave on the hub cluster.

Changes:

• Upgrades the Istio tooling version used by the multi-cloud deployment script.
• Refactors Fleet placement so the namespace is placed independently (NamespaceOnly) and app resources are placed via a namespaced ResourcePlacement.
• Adds a hub webhook failurePolicy workaround to allow applying placement resources when the hub has no running webhook endpoints; updates base placement selectors to use labels.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 4 comments.

File	Description
documentdb-playground/multi-cloud-deployment/documentdb-cluster.yaml	Splits namespace placement (CRP) from application resource placement (RP) for Fleet.
documentdb-playground/multi-cloud-deployment/documentdb-base.yaml	Switches some Fleet selectors to label-based selection and updates CNPG CRD list.
documentdb-playground/multi-cloud-deployment/deploy.sh	Upgrades Istio version and adjusts istioctl installation flow.
documentdb-playground/multi-cloud-deployment/deploy-documentdb.sh	Adds hub validating webhook workaround and updates placement resource names.

[documentdb-triage-tool]

🤖 Auto-triaged by documentdb-triage-tool.

Applied: ecosystem, enhancement
Project fields suggested: Component playground · Priority P2 · Effort M · Status Needs Review
Confidence: 0.82 (mixed)

Reasoning

component from path globs (playground); effort from diff stats (81+31 LOC, 4 files); LLM: Fixes a broken istio configuration in the multi-cloud playground by upgrading the version and adding a webhook workaround for fleet.

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